Extruder fans not turning on? Manta M8P V2.0?

Basic Information:

Printer Model: tronxy x5s / custom
MCU / Printerboard: manta m8p
Host / SBC CB1
klippy.log

Fill out above information and in all cases attach your klippy.log file (use zip to compress it, if too big). Pasting your printer.cfg is not needed
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Describe your issue:

Hey all, new to Klipper here so maybe this is common but

Strange issue, all the fans that arent Fan0 part cooling fan are sometimes not turning on/ staying on

some are extruder fans forwater pump/radiator fan, one for extruder on PSU and one are for controller fan for MCU board cooling

The issue is I think if i start a print or if the print fails sometimes (or i cancel it or it gets cancelled) it seems even though klipper is reporting the fans are still on they are not, no green “activity” light on the manta and no voltage output that i can tell?

The issue is i really need the water pump to stay on or come on when the print starts because i Risk damaging the hot end if i power the heater with no coolant flow/ cooling fan

Cheers

I cant seem to upload the klippy.log because the file is too big?

Hello @Mantatron !

Thought about compress it?

1 Like

hey Eddy!

Sure, i just needed to be on my PC to do it
klippy.zip (1.2 MB)

  • here is the klippy.log compressed

I think I have given older log? looking inside it there isn’t my current printer.cfg in there - I have several klippy.logs but they only go to 11/04/25, there is no log from today? i have attached latest which seems to have my current fan setup
klippy.log.2025-04-11.log (7.7 MB)

might as well just give you printer.cfg as well…
printer.cfg (12.1 KB)

ok, seems to be related to reboot or firmware halt - when the systems restarts I can see the fans should be spinning but they dont, I must be missing something

normal operation everything works fine, its only during rebooot/restart/firmwar_restart

Only power off from plug and back on resets this fault (as in, the fans start to spin again because of elevated temperatures) - im guessing this is something to do with Manta M8P?

Just to be sure, you are aware that:

Hey Sineos, I was not aware - is this incorrect use of Heater_Fan and Controller_Fan? - the issue is when a print fails it causes some form of state that disables the fans - even if the temperatures are over 200C etc even after soft reset

I believe this is a communication issue possibly between CB1 and MCU on the manta, when power is hard reset the fans kick back in automatically, as if CB1 was in a fault state or had incorrect temperature?

I would have thought the default state of these fans would be “on” at a point of comms loss for safety? or maybe this is MCU fail outputs low for safety possibly

Hey Sineos, I had not seen shutdown_speed - I will try this now

Right, plot thickens - I updated the following:

Fan1

[heater_fan Water_Pump]
pin: PF9
heater: extruder
heater_temp: 50
max_power: 1.0
fan_speed: 1
kick_start_time: 0.5
shutdown_speed: 1.0

Fan2

[controller_fan MCU_Fan]
pin: PF6
max_power: 1.0
fan_speed: 1
kick_start_time: 0.5
stepper: stepper_x, stepper_y
shutdown_speed: 1.0

Fan3

[heater_fan Radiator_Fan]
pin: PF8
heater: extruder
heater_temp: 50
max_power: 1.0
fan_speed: 1
kick_start_time: 0.5
shutdown_speed: 1.0

Fan4

[heater_fan PSU_fan]
pin: PA4
heater: heater_bed, extruder
max_power: 1.0
fan_speed: 1
kick_start_time: 0.5
shutdown_speed: 1.0

here is events that happened after hard reset/ Power cycle:

printer powered on - bltouch does self test - no fans on - so far good

homed X/Y/Z - correct MCU fan turns on - so far good

Heated extruder to 70C - all fans turn off, no fans at all?

heater goes up to 70C, i can touch the hot end and feel it is hot

I go to check Manta and no green led’s showing any output on fan headers etc?

also stepper drivers still active, so controller_fan MCU fan should be on but it turned itself off as soon as I set extruder temp 70C

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@EddyMI3D apologies will use that from now on:

weird part is, Moonraker reports correct action, all fans should be on but they are not

Please provide a recent klippy.log.
Seems strange, your configuration looks sound.

Try cutting down to the bare minimum, e.g.:

[heater_fan Water_Pump]
pin: PF9
shutdown_speed: 1.0

or try manually controlled configs to validate the function:

[fan_generic Water_Pump]
pin: PF9
shutdown_speed: 1.0

I think you might be right - i will try

one thing to confirm, I have tried every combination, turn off, turn on, press X/Y/Z axis, heated bed etc and all fan is working as expected apart from Extruder, this is the only thing that turns off all fans

if i do not turn on extruder everything works as expected, with fans coming on when steppers enabled/temps going over 50C and then turning off when disabled/temp drops below theshold

im not sure if there is a maximum amount of defintions for calling Heater_Fan: “Extruder”? because I call it 3 times, I have deleted the call but of course Heater_Fan defaults to extruder

I have tried removing " Extruder" from Heater_fan PSU Fan and it finally works expected!

It seems not to like calling temp request from both Heater Fan in 3 places?

Edited - not Controller Fan MCU, it was Heater Fan PSU

having setup the printer properly, run with and without Macros and performed successful prints I have another Klippy - the issue doesnt seem to be related to what fans.PIDS are called in printer.cfg

the issue seems to be repeatable, to one scenario - if I change any file in the /config folder and save, if I turn just Extruder on all fans will turn off regardless of temp

I can overcome this 100% of the time by power cycling the CB1/MCU, which im just doing now and things are running fine - no other issues

have attached recent klippy with hopefully more info now its been running etc

had a weird issue with file size and an invalid software version but those were solved with Hard_

Recovery, the issue with fans still exists but the software is fantastic despite this, extremely happy thank you for support

klippy (3).zip (2.2 MB)